diff --git a/packages/api-extractor-model/src/model/ApiPackage.ts b/packages/api-extractor-model/src/model/ApiPackage.ts
index 89f8b4372..e55b843b9 100644
--- a/packages/api-extractor-model/src/model/ApiPackage.ts
+++ b/packages/api-extractor-model/src/model/ApiPackage.ts
@@ -294,7 +294,11 @@ export class ApiPackage extends ApiItemContainerMixin(ApiNameMixin(ApiDocumented
 
 		const tsdocConfiguration: TSDocConfiguration = new TSDocConfiguration();
 
-		if (versionToDeserialize >= ApiJsonSchemaVersion.V_1004 && 'tsdocConfig' in jsonObject.metadata) {
+		if (
+			versionToDeserialize >= ApiJsonSchemaVersion.V_1004 &&
+			'tsdocConfig' in jsonObject.metadata &&
+			'$schema' in jsonObject.metadata.tsdocConfig
+		) {
 			const tsdocConfigFile: TSDocConfigFile = TSDocConfigFile.loadFromObject(jsonObject.metadata.tsdocConfig);
 			if (tsdocConfigFile.hasErrors) {
 				throw new Error(`Error loading ${apiJsonFilename}:\n` + tsdocConfigFile.getErrorSummary());